How much does it cost to flush a water heater?

Short answer

Flushing a water heater yourself costs $0 to $15. A plumber charges $100 to $200. The only thing you might need to buy is a garden hose, and most homes already have one. The job takes 30 to 60 minutes either way, and most of that is waiting for the tank to drain, so a plumber's price is mostly the trip to your house.

Cost breakdown

The DIY total is the price of a garden hose if you don't own one. A bucket and a flathead screwdriver round out the kit, and almost every home has both.

What drives the cost

• The service call. Most of a plumber's price covers getting to your house and the minimum charge for a visit. The flush itself is a small part of it, which is why the price doesn't drop much for a small tank.
• What the plumber finds. A stuck or crumbling drain valve, a relief valve that drips, or a worn anode rod turns a flush into a repair visit. Ask for a price before they go ahead with anything beyond the flush.
• Where the tank sits. A tank in an attic or a tight crawl space takes longer to reach and to drain, and some plumbers charge more for it.
• Bundling. Flushing is often included when a plumber is already there for another job, or sold as part of a yearly water heater service. If you're having other work done, ask.
• Your area. Plumbers in big cities charge more for the same visit than plumbers in small towns.

DIY vs. pro

Doing it yourself makes sense for most homes. Once you know how often to flush a water heater and have done it once, it's a yearly chore on the level of changing a filter. The savings are the whole plumber's fee, every year.

Hire it out when the drain valve is stuck, when the tank is old and has gone years without a flush, when you'd rather not handle a gas pilot, or when you want someone to check the relief valve and anode rod at the same time. A plumber who does all of that in a single visit is good value, because each of those checks on its own would cost a trip.

FAQ

Is it worth paying a plumber to flush a water heater?

For a healthy tank, no. The job needs no special tools or skill. It's worth paying when the tank is old, the valve is stuck, or you want the rest of the heater checked in the same visit.

What else does a plumber do during a water heater flush?

A good one lifts the relief valve to check it opens, looks at the anode rod if it's easy to reach, checks the burner or elements, and looks for rust or moisture around the base. Those checks are often why the visit is worth the fee.

Can flushing damage an old water heater?

It can expose problems that were already there. Sediment sometimes plugs a pinhole leak or a weak drain valve, and flushing it out lets the leak show. That is a sign the tank was near the end anyway, not damage from the flush.

Does flushing a water heater lower the energy bill?

A little, by removing the sediment that the burner or element has to heat through. The bigger saving is a tank that lasts its full life instead of failing early.